Means for rebuilding furnace roofs



July 26, 1932. N. THOMPSON ET AL 2 Sheets-Sheet 1 Z0 H 1 1s) -15 Patented July 26 1932 PATENT OFFICE NORMAN THOMPSO B' AND CARL JI JHNSON, OF DULUTH, MINNESOTA mnans non nnrumome summon 30038 Application filed December 26, 1929. Serial No. 416,641.

Our invention relates to open hearth furnaces and more especially. to a means and method of rebuilding furnace roofs. Our invention is adapted for use in connection e'with open-hearth furnaces which are constructed mainly of brick work and in which the roof particularly is an arch struction. After such a furnace has beeri in operation for a considerable length of time the arched roof burns thin and after repeated contraction and expansion due to changes in temperatures between heats this arch cracks or breaks and fre uently falls in and it becomes necessary to uild another arch. For the rebuilding of these arches forms are necessary and the usual practiceis to build up such forms and due to the limited space within the furnace, itis'necessary that in removing them they must'be demolished or so 30 damaged that they have no further usefulness, which results in a considerable cost of labor as well as loss of time for the construction and removal of these forms for each rebuilt roof. Our invention has been conceived and perfected with a view to overcoming the difliculties just mentioned and provide improved means \and method of rebuilding furnace roofs, using forms which can be removed completely without damage or loss of time and with the attendant saving of cost, and reduction of overhead expense during the time the furnace mustnecessarily be out of service. Itis an object of our invention to rovide an improved method and 'means or the patching or rebuilding of an open hearth furnace roof in ,which the forms can be removed and used again. i

It is another object of our invention to provide improved means for rebuilding furnace roofs, by the use of which the damage to the walls of the furnace is reduced to a,

minimum.

It is a further object of our invention to provide forms for patching furnace roofs which can be easily put in place, and easily removed without damage.

It is a further object to provide a form construction in which the forms can be used 0 repeatedly.

of brick con cation thereto of skew-back irons 16 w A further object of our invention is to provide a method of reconstructing furnace roofs which is economical both in expenditure of time and material. 1

A. further object of our invention is the provision of a method for rebuilding furnace roofs wherein the forms and their supports may1 be used repeatedly without being; dama e Other objects and advanta es will become obvious from the following escription and specification, in which we refer to the accompanying drawings wherein- Flgure l is a sectional plan view of an open hearth furnace embodying our invention;

Figure 2 is a sectional elevation taken along the line 22 of Figure 1;

Figure 3 is a view similar to Figure 2 showing the invention applied to a furnace of a slightly modified construction;

Figure 4 is a segmental enlarged view of one of the supporting hooks employed in connection with theinvention, and.

Figure 5 is an enlarged view and side elevation of the supporting hook shown in Figure 4.

As illustrated in the drawings, the reference numeral 10 indicates the foundation of an open hearth furnace of general construction. Extending upwardly from the outer wallof the hearth foundation are a plurality of buck stays which are braced at their upper extremities by means of transversely extending members 12. The buck stays 11 and bracing members 12 serve to support the side walls of the furnace.

The side walls of the furnace are formed with a plurality. of charging openings 15 which normally are closed by furnace doors but, as shown, the latter members have been removed in order the more clearly to indicate the installation and construction of the parts comprising the invention. The tops of the furnace charging openings, as lllustrated m' Figures 2 and 3, are bridged over by means of brick work 14, held in place by the appliich extend along the top outer edges of the furnace and comprise a port-ion of the outerwall.

' To assist in supporting the skew-backs and maintaining the latter in place, there are provided a plurality of supportingbolts 13 extending downwardly from the upper frame work of the furnace.

The inner faces of the brick work portions 14, 14 are beveled as illustrated in Figures 2 and 3 and a furnace roof 14a of arched transverse configuration extends between the oppositely facing surfaces of the brick portions 14, and is supported by wedging engagement with the beveled surfaces thereof. As heretofore pointed out the furnace roof, after protracted operation of the furnace, becomes likely to break and fall in, and also, as has already'been stated, the present invention is directed toward the provision of means for supporting thebroken in furnace roof during the course of repairing it.

As illustrated in Figure 2, a form 22 having an upper surface arched complementary to the undersurface of the furnace roof 14a, is inserted in the furnace through the charging openings 15 and is adapted to be supporte in position to have the roof laid upon it, by means of apparatus which will now be described. Supporting hooks 18 are clamped onto the skew-back irons 16 at points located above the charging openings and the lower extremities of the hook portions are bifurcated as shown at 18a (Fig. 5) to receive rail sections 19 or other suitable load carrying members. The rail sections are maintained in assembled position relatively to the supporting hooks by means of wedges 20, which span the opening formed by the bifurcation, the latter being supported by the leg members of the supporting. hooks as illustrated in Figures 4.- and 5. As shown in Figure 1, the invention contemplates the installation of a number of these supporting hooks and rail sections 19 throughout the length of the furnace and in order to support the forms 22 it is intended to surmount upon the rail sections 19 a suitable number of additional rail sections 21 extending at right I angles to the lower sections.

In the operation of repairing a caved or fallen in furnace roof, the forms 22 will be placed upon the form supports 21 at points located directly beneath the break or opening in the furnace roof, a suitable number of forms being provided for supporting the brick work which is to be inserted into the opening in-the roof. In the type of furnace illustrated in Figures 1 and 2 the presence of the charging openings at diametrically opposite points in the side walls of the furnace permits the ready insertion of the repair.

parts 19, 21 and 22. c

There are many furnaces in use of the type illustrated in Figure 3 in which charging doors are provided along one side only of the furnace and in this latter type of construction it will be necessary to'break away a portion of the furnace wall opposite the aeeaaea charging openings as illustrated in Figure 3. As therein shown the rail sections 19 are supported .in a sloping position through the charging openings and the broken out portionsof the opposite furnace wall, and upon these sloping members are mounted the supporting sections 21 and the arched forms 22. When this stage of the assemblage is reached the lower sloping extremities of the sections 19 are raised to enter the bifurcations in the supporting hooks and the wedges are then inserted to maintain the forms in proper position within the furnace.

To serve as an aid in lifting the forms into position the latter may be provided with rings disposed in countersunk pockets formed in the upper surface of the forms and it will be appreciated that in installing the forms in position the rings are readily accessible thrgugh the opening or break in the furnace roo The removal of the forms is obvious. The outer ends of the rails 21 are lifted slightly with a crane or by other suitable means and the wedges 20 are knocked out. The rails can then be lowered carrying with them the sections 21 and forms 22 and removed by passing them through the charging doorways or openings. The forms thus removed are complete and undamaged and are available for use again in the arched formation of other furnaces and may be so used indefinite- 2 1y. The rails and books with their wedges of course, undamaged and can likewise are,

It-is thus seen that be used over and over.

in the construction of an arch using the forms and supports associated therewith that there is no loss of material since there is no breaking or demolition or damage of any sort.

Changes and modifications in the above described method and in the design and construction of the illustrated devices may be made without departing from the true scope of the invention as set forth in the appended claims.

We claim:

1. In a form work for furnace roofs and the like, in combination, a plurality of forms extending substantially the width of said furnace, cross supports for said forms, a plurality of rails for supporting said cross supports and said forms, and adjustable supporttion, comprising, in combination, a plurality of hooks secured to the sides of said furnace,

adjustable wedges in said hooks, a plurality of rails disposed across the furnace and supported by pairs of said hooks and adapted to hear on said wedges, cross members extending transversely of said rails, and a plurality of forms extending substantially the Width of said furnace, there being apertures in said hooks adapted to receive the protruding ends of said rails.

3. A form work for rebuilding furnaces having side walls, a roof, and charging doors in said walls, comprising in combination, a plurality of spaced hooks supported by said walls, a plurality of spaced rails supported adjacent their ends by means seated in pairs of said hooks, cross members resting on said rails, a plurality of forms supported by said cross members, said hooks ea'ch having a seating portion, there being a recess in said hooks adjacent said seating portion adapted to receive said rails, and a plurality of wedges adapted to rest in said seats and' support said rails and said hooks.

4;. A form work for rebuilding open hearth furnaces having side walls, a roof, and charging doors in said side walls comprising, in combination, a plurality of spaced hooks sup I ported by said side walls, said hooks each having an aperture adjacent an end thereof and a seating portion adjacent said aperture,

wedges adaptedto rest in said seats, a plurality of rails extendingacross said furnace and supported by said wedges and hooks and extending through the apertures therein, so cross members supported by and extending transversely of said rails, and a plurality of forms extending transversely of said cross members, said forms adapted to be inserted in said furnaces through said charging doors. 5. A form work for rebuilding open hearth furnaces having sidewalls, a roof, and charging doors, comprising in combination, a plurality of spaced hook memberssupported at their upper ends by said side walls, the lower portion of said hooks forming a seat, there being a recess in said hooks adjacent said seating portions, a plurality of rails extending across said furnace and supported advjacent their ends in pairs of said hooks, wedges adapted to rest in said seats and adjustably support said rails, supporting members extending across said rails, and a plurality of forms extending substantially the width of said furnace and supported on said cross members, said formshaving a width adapting them to be inserted through said charging doors and to be removed therethrough.

Signed at Duluth, Minn., this 20th day of September, 1929.

NORMAN THOMPSON. CARL JOHNSON. 

